The x-ray mass-attenuation coefficient of copper was measured at 108 energies between 5 and 20 keV using synchrotron radiation. The measurements are accurate to between 0.09 and 4.5 %, with most measurements being accurate to better than 0.12%. The imaginary component of the form factor of copper was also determined after subtracting the attenuation contribution due to scattering. Measurements were made over an extended range of experimental parameter space, allowing us to correct for several systematic errors present in the data. These results represent the most extensive and accurate dataset of their type for copper in the literature and include the important and widely studied region of the K-edge and x-ray absorption fine structure. The results are compared with current theoretical tabulations as well as previous experimental measurements and expose inadequacies in both.

Can we test QED? Is it true? We are the only group to test QED in Australia and have just had a breakthrough reported in Physics Today. This was an international team effort and doctoral thesis work but also with contributions from an Honours/Masters student. 2. How can we get structural information from an isolated quantum system-molecule, gas or non-crystalline solid? We have been the world leaders in extracting structural and quantum information from atomic, molecular and organometallic (i.e. biophysical) systems with advanced experiments and analysis, advancing the techniques used by more than 30% of all synchrotron researchers across the world. 3. Can I develop or invent a new field of physics? Yes but probably not in Masters! Recent doctoral students have developed new fields of non-destructive nanoroughness measurement; and electron inelastic scattering (mean free path) experiment and theory; or made major developments in dominant fields of X-ray science or relativistic Quantum Mechanics. • Facilities: X-ray labs; Synchrotrons around the world & Melbourne; EBIT labs around the world. Our local laboratories develop new technology in-house, & ask fundamental questions about the universe & matter. • Two honours students (2005) produced 3 major papers from honours (one high profile Phys. Lett.). Three honours students (2006) got the best experimental thesis in the School (Ramm Prize), and one of the top 3 theory theses. Both students in 2008 got top marks in theory and experiment. These great results reflect on them, the potential of the field & our group. Martin de Jonge was awarded the Chancellor's Prize (best Doctoral Thesis at Melbourne University), 'Best Synchrotron Thesis in Australia', flew off to an exciting career at the Advanced Photon Source (Chicago) & has now returned to get first light on the Australian Synchrotron on a key beamline. We receive national & international awards for group achievements. Our experiments are two orders of magnitude more accurate than all earlier publications in the field. 1 This has opened up exciting new opportunities & opened our eyes to new phenomena and new ways of testing earlier assumptions. Our experiments have been the first to measure scattering 2 & synchrotron bandwidth in photoabsorption experiments, have redefined the international standards for (powder) diffraction 3 , and have placed the field of X-ray Absorption Fine Structure (XAFS) on an absolute footing for the first time. Our relativistic atomic theory and tabulation 4 is the most successful currently available in terms of agreement with experiment. Theory must be based on condensed matter physics near absorption edges to explain detailed oscillations, which in turn raises new questions. Honours students have developed new theory & computational tools for condensed matter science, including the first extended XAFS solution avoiding 'muffin-tin' approximations 5 & the largest (organometallic) XAFS modelled without this assumption, 6 with major implications for biological

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Can current experimental techniques and analytical procedures produce x-ray absorption fine structure (XAFS) which is independent of the beam line or synchrotron used? We investigate the consequence upon XAFS interpretation of typical systematic errors, including determination of the edge energy, detector response and synchrotron bandwidth. Using the highest accuracy data set of the mass-attenuation coefficient collected so far, we consider a series of systematic effects in the analyses of both the near-edge and extended energy regions of the spectrum. We investigate whether conclusions derived from an experiment using a given analytical procedure are consistent when performed on different synchrotron beam lines. We find that the effectiveness of common XAFS analysis is limited by experimental and data reduction techniques, particularly relating to determinations of photon energy. By correcting for all major systematic errors in XAFS data, one can determine bond lengths more robustly and with greater accuracy.